Free floating ram members for punch presses and the like



Sept. 5, 1967 v R. E. LANG 3,339,481

I FREE FLOATING RAM MEMBERS FOR PUNCH PRESSES AND THE LIKE Filed Feb.15, 1966 2 Sheets-Sheet IN VENTOR. RICHARD E. LANG Buff/(aw ATTORNEY R.E. LANG Sept. 5, 1967 FREE FLOATING RAM MEMBERS FOR PUNCH PRESSES ANDTHE LIKE 2 Sheets-Sheet 2 Filed Feb. 15, 1966 N: o= Mg INVENTOR. RICHARDE. LANG fi/M M ATTORNEY United States Patent 3,339,481 FREE FLOATING RAMMEMBERS FOR PUNCH PRESSES AND THE LIKE Richard E. Lang, 100 GreenbriarDrive, Carnegie, Pa. 15106 Filed Feb. 15, 1966, Ser. No. 527,586 6Claims. (Cl. 100-214) This invention relates to apparatus of the typehaving a ram member adapted to perform work-operations, such as,piercing, stapling and the like, and more particularly to improvementsin the drive and in the support for said rams.

Although not limited thereto, the present invention is particularlyadapted for use in punch presses. As is known, punch presses areemployed to pierce openings in, for example, structural members such asH-beams, I-beams and the like. The punch press includes a punch bitcarried by a ram member, and a die block having a die opening positionedto receive the punch bit. The ram member is powered to move the punchbit toward and into the die opening during the power or piercing stroke,and is retracted in the opposite direction during the return stroke.

In prior art punch presses, the ram member is powered both toward thedie block and away from the die block. The ram member is powered towardthe die block in order to pierce the workpiece. The ram member must alsobe powered away from the die block in order to extricate the punch bitfrom the workpiece. Consequently, in one cycle of operation, the rammember undergoes one reciprocation, that is, it is moved sequentiallytoward and then away from the die block.

As is known, the punch bit must be lowered and centered over the exactpoint on the workpiece at which an opening is to be pierced. The rammember and the punch bit may be lowered manually. However, since the rammember is always connected to its drive means, great difficulty isencountered in lowering the ram member and the punch bit manually. Thepunch bit may also be lowered by quickly energizing and deenergizing thedrive means. One disadvantage of employing the drive means for loweringthe punch bit, is that the punch bit may be lowered'too far causing thebit to be embedded in the workpiece, usually at the wrong location. Inthis instance, the punch bit may be elevated manually, with greatdifficulty, or it maybe elevated by reversing the drive means if areversing mechanism is provided. I

- Punch presses wherein the ram member is always connected to the drivemeans, have a further disadvantage. It should be evident that when thepunch bit is in a lowered positiomless than the full impact capacity ofthe drive means is available for piercing the workpiece.

Accordingly, as an overall object, the present invention seeks toprovide an improved drive and support arrangement for ram members.

Another object of the invention is to provide an improved support meansfor a ram member wherein the ram member is freely movable in itsdirection of reciprocation whereby the position of a ram member relativeto the workpiece may be readily and easily adjusted.

A further object of the invention is to provide an improved ram drivewhich imparts its full impact capacity to the ram regardless of theposition of the ram relative to the drive.

Still another object of the invention is to provide improved means forretracting the ram, which means is operable only during the returnstroke of the drive means and, hence does not interfere with thepositioning of the ram relative to the workpiece prior to a powerstroke.

The present invention is described and illustrated herein in conjunctionwith a punch press which pierces open- Patented Sept. 5, 1967 ings inworkpieces. It should be noted, however, that the principles of thepresent invention may be adapted to other apparatus whereinwork-operations, such as, cutting, stapling, shaping, and the like areperformed.

As described and illustrated herein, apparatus, such as, a punch press,is provided having a ram member, one end of which is adapted to performa work-operation on a workpiece disposed adjacent thereto. The rammember is supported by a frame and is movable reciprocally such thatduring one cycle of operation of the apparatus, the rammember is movedin one direction during a power stroke and in the opposite directionduring a return stroke.

In accordance with the present invention, the ram member is providedwith a generally rectangular opening whose periphery is defined byopposed side faces and upper and lower end faces. A pitman memberresides within the opening and has a generally rectangular configurationcorresponding to the configuration of the opening. Eccentric rotarymeans is slideably engaged with the pitman member and serves to move thesame in a circular path whereby the pitman member is moved sequentiallytoward one of the side faces and then into engagement with the lower endface of the ram during the power stroke, and then toward the other ofthe side faces during the return stroke. The pitman member is smallerthan the opening whereby its sides are spaced from the correspondingside faces of the opening when the pitman member is in a centeredposition relative to the opposed side faces. Consequently, the rammember is freely movable in its direction of reciprocation whereby theposition of a ram member relative to the workpiece may be adjusted priorto the power stroke. Cooperating catch means are provided for moving theram member in the opposite direction, that is, retracting the ram memberaway from the workpiece. The cooperating catch means are operable onlyduring the return stroke and hence does not interfere with thepositioning of the ram member relative to the workpiece. Drive means isprovided including actuating means for rotating the eccentric rotarymeans through a single revolution and hence, for moving the ram memberthrough a single reciprocation. The overall arrangement is such that theram member may be lowered and thereby centered over a point on aworkpiece at which an opening is to be pierced. Thereafter, theactuating means is depressed so that the drive means rotates theeccentric rotary means through a single revolution during which thepitman member strikes the ram member to pierce the workpiece andthereafter the cooperating catch means are engaged to retract the rammember and thereby extricate the punch bit from the workpiece.

The above and other objects and advantages of the present invention willbecome apparent from the following detailed description by reference tothe accompanying drawings, in which:

FIGURE 1 is a schematic side view of a punch press provided with theapparatus of the present invention;

FIG. 2 is a front elevation view illustrating the sup port and drivearrangement for a ram member having a punch bit secured at one endthereof;

FIGS. 3A3H are schematic front views, similar to FIG. 2, illustratingone cycle of operation of the apparatus of the invention;

FIG. 4 is a schematic front view, similar toFIG. 2, illustrating analternative arrangement of the cooperating catch means of the invention;

FIGS. 5 and 6 are fragmentary front elevation views, similar to FIG. 2,illustrating a further alternative arrangement of the cooperating catchmeans of the invention; and

FIG. 7 is a fragmentary elevation view, partially in cross section,illustrating the cooperation catch meansv of FIG. 6, on an enlargedscale.

Reference is now directed to FIG. 1, wherein there is illustrated apunch press generally indicated by the numeral 10. The punch pressincludes a C-shaped main frame 12 having an upper arm 14 and a lower arm16 and a power section schematically illustrated at 18. The powersection 18 normally is carried at the rear of the main frame 12. At theforward end of the upper arm 14 there is provided a housing 20 whichsupports a ram member (not visible) to which is attached a punch holder22 carrying a punch bit 24. A shaft 26, driven by the power section 18,extends forwardly along the upper arm 14 and is connected to the rammember as will be described. At the forward end of the lower arm 16there is provided a die block 28 which preferably comprises thereversible die block described and claimed in my US. Patent No.3,222,973, issued Dec. 14, 1965, and entitled, Reversible Die Block. Asdescribed in the aforesaid US. Patent No. 3,222,973, the die block 28may be positioned as shown in FIG. 1, to support a structural member,such as the I-beam 29 so as to pierce openings in the flange of theI-beam 29. The die block 28 may be repositioned such that the flanges ofthe I-beam may also be pierced.

The power section 18 is connected to the shaft 26 and serves toreciprocate the punch holder 22 in a vertical direction. Thus, during apower stroke, the punch holder 22 and, hence, the punch bit 24 areforced downwardly toward the I-beam 29 so as to pierce an openingtherein. During the return stroke, the punch holder 22 is retracted soas to extricate the punch bit 24 from the opening pierced in the I-beam29. The power section 18 consists of a flywheel 30 which is connected toa driven pulley 32, for example, by means of belts or chains 34. Thedriven pulley 32 is connected to and driven by a motor schematicallyillustrated at 36. Interposed between the flywheel 30 and the shaft 26is a clutch 38 of the type which causes the shaft 26 to rotate through asingle revolution. Associated with the clutch 38 is clutch controlapparatus schematically illustrated at 40 and an actuating mechanismsuch as a foot pedal 42. The construction of the clutch 38 and theclutch control apparatus 40 are well known in the art and, therefore, acomplete description thereof is not believed to be necessary.

The overall arrangement is such that when the foot pedal 42 isdepressed, the clutch control 40 causes the clutch 38 to be engagedwhereupon the shaft 26 rotates through a single revolution, that is,360, whereupon the clutch 38 is disengaged. During the single revolutionof the shaft 26, the punch holder 22 undergoes one reciprocation, thatis, the holder 22 is moved toward the die 28 and then retracted awayfrom the die 28 into its normally elevated position.

Referring now to FIG. 2, the housing or frame 20 comprises spaced,substantially parallel side pieces 44 and a crosspiece 46 connected incorresponding ends of the side pieces 44. A ram member 48 is disposedbetween and slideably engaged with the side pieces 44, the arrangementbeing such that the ram member 48 is slideable in a vertical direction.The ram member 48 has a generally rectangular opening 50 whose peripheryis defined by opposed side faces 52, 54 and lower and upper end faces56, 58.

Residing within the generally rectangular opening 50 is a pitman member60 having a generally rectangular configuration corresponding to theconfiguration of the opening 50. Accordingly, the pitman member 60 hasopposite sides 62, 64 and lower and upper ends 66, 68 corresponding,respectively, to the opposed side faces 52, 54 and the lower and upperend faces 56, 58 of the ram member 48. The pitman member 60, however, issmaller than the opening 50 and, hence, the position of the ram member48 is adjustable in a vertical direction through a distance indicated bythe dimension line 70 connecting the lower face of the full-line anddotted-line illustrations of the punch bit 24. A handle 72 is secured tothe ram member 48 and extends through a vertical slot 74 provided in oneof the side pieces 44. The handle 72 is employed to raise and lower theram member to position the punch bit 24 relative to the workpiece beingpierced. At the top of the frame 20 there is provided a counterbalancemechanism which comprises a shaft 76 extending through the crosspiece 46and secured to the ram member 48. The shaft 76 is surrounded by a coilspring 78 which is interposed between the upper surface of the frame 20and an enlarged plate 80 threaded onto the upper end of the shaft 76.Rotation of the plate 80 in the appropriate direction will cause thecoil spring 78 to be compressed or to be relaxed so as to counterbalancethe weight of the ram member 48.

Eccentric rotary means 82 is slideably engaged with the pitman member 60and serves to move the pitman member 60 in a circular path. Theeccentric rotary means 82 comprises an eccentric cam member 84 slideablyengaged in a circular opening 86 provided in the pitman member 60. Theeccentric cam member 84 is keyed or otherwise secured to the shaft 26and has a geometric center at 88 which is spaced from the rotationalaxis 90 of the shaft 26. The overall arrangement is such that as theshaft 26 is rotated through 360, the pitman member 60 will be displacedlaterally and vertically through a distance equal to twice the radialdistance between the geometric center 88 of the cam member 84 and therotational axis 90 of the shaft 26. While the pitman member 60 is movedalong its circular path of travel, the ram member 48 is caused toreciprocate vertically in a manner which will be described inconjunction with FIGS. 3A-3H, inclusive.

During the power stroke, the ram member 48 is moved downwardly through adistance approximately equal to the distance indicated by the dimensionline 70. During the return stroke, cooperating catch means 92, carriedby the pitman member 60 and the ram member 48, are engaged to retractthe ram member 48 through a distance approximately equal to the distanceindicated by the dimension line 70. The ram member 48 is returned to theposition illustrated in FIG. 2.

In the preferred embodiment, the cooperating catch means 92 comprise apin 94 projecting from the side face 54 of the ram member 48 and a notch96 cut in the side 64 of the pitman member 60. The pin 94 is preferablynarrower than the notch 96 and has a bottom face 98 spaced above thelower end face 56 by a distance indicated at 100. The notch 96 has alower shoulder 102 which is spaced above the lower end 66 of the pitmanmember 60 by a distance indicated at 104. The distance 100 is greaterthan the distance 104. As will be described, this differential spacingpermits the lower shoulder 102 to move laterally beneath and engage thebottom face 98 during the return stroke so that the pitman member 60 isconnected to and raises the ram member 48 to substantially the positionshown in FIG. 2.

The pitman member 60 is provided with an arcuate corner 106 which isdisposed on the same side of the ram member 48 as the notch 96. If, forsome unforeseen reason, the pin 94 does not engage the notch 96, theabsence of material at the arcuate corner 106, permits the pitman member60 to engage the side face 54 and rotate about the cam member 84 wherebythe pin 94 is by-passed. It should be evident that if the pitman member60 could not rotate about the cam member 84, the pitman member 60 wouldjam causing considerable damage to the press 10.

Reference is now directed to FIGS. 3A-3H, inclusive, for a descriptionof one cycle of operation. FIGS. 3A-3H are schematic front viewsillustrating certain positions of the ram member 48, the pitman member60 and the eccentric rotary means 82.

In FIG. 3A, the eccentric rotary means 82 is shown in its initial topdead center and the ram member 48 is shown in an elevated position. Thepunch bit 24 is shown spaced above a workpiece 108 which rests on a dieblock 110 having a die opening 112.

As shown in FIG. 3B, the ram member 48 is lowered, by means of thehandle 72, such that the punch bit 24 is directly above that point onthe workpiece 108 at which an opening is to be pierced. At this time,the foot pedal 42 (FIG. 1) is depressed to cause the eccentric rotarymeans 82 to be rotated through a single revolution.

In FIG. 3C, the eccentric rotary means 82 has rotated through 90 in aclockwise direction. Accordingly, the pitman member 60 is movedlaterally into engagement with the sidetface 52 of the ram member 48 anddownwardly into engagement with the lower end face 56.

As can be seen in FIG. 3D, the eccentric rotary means 82 has movedthrough an additional 90 in a clockwise direction. The pitman member 60,already engaged with the lower end face 56. of the ram member 48, ismoved downwardly causing the ram member 48 to move therewith. The punchbit 24, therefore, is forced through the workpiece 108 causing anopening to be pierced therein. At this point in the operation, thepitman member 60 is centered in the generally rectangular opening 50,that is, equidistantly spaced from the side faces 52, 54 of the rammember 48. Also, the pin 94 is disposed adjacent the notch 96preparatory to entering the same.

In FIG. 3E, the eccentric rotary means 82 has rotated through anadditional 45 in a clockwise direction. During this rotation, the pitmanmember 60 is moved laterally to the left of FIG. 3B and upwardly. As canbe seen, the lower shoulder 102 of the notch 96 has moved beneath andupwardly into engagement with the bottom face 98 of the pin member 94.At this time, the pitman member 60 is connected to the ram member 48 andthe ram member 48 commences to move upwardly away from the workpiece108.

In FIG. 3F, the eccentric rotary means 82 has rotated through anadditional 45 in a clockwise direction. During this amount of rotation,the pitman member 60 has moved to the left of FIG. 3F into engagementwith the side face 54 of the ram member 48. Simultaneous with thelateral movement of the pitman member 60, the ram member 48 is movedupwardly by virtue of the connection between the pin member 94 and thenotch 96. The punch bit 24 has been extricated from the openingpreviously punched in the workpiece 108.

In FIG. 3G, the eccentric rotary means 82 is rotated through anadditional 45 in a clockwise direction. The ram member 48 and hence thepunch bit 24 are further elevated away from the workpiece 108. Thepitman member 60 also is moved laterally to the right of FIG. 3G so thatthe pin member 94 is being moved out of engagement with the notch 96.

Finally, in FIG. 3H,- the eccentric rotary means 82 is moved through anadditonal 45 in a clockwise direction to bring it to its initial topdead center position. At this time, the ram member 48 and the punch bit24 are in their maximum elevated positions. Furthermore, the pitmanmember is again centered with respect to the generally rectangularopening 50 so that the pin 94 is disengaged from the notch 96. At thistime, the workpiece 108 may be repositioned for the piercing of anotheropening. Inasmuch as the pin 94 is disengaged from the notch 96, the rammember 48 is freely movable in a vertical direction so that the punchbit 24 may be lowered adjacent to a new point on the workpiece 108preparatory to punching another opening therein.

Alternative arrangements Reference is now directed to FIG. 4 and toFIGS. 5-7, inclusive, wherein alternative arrangements of thecooperating catch means are illustrated.

As can be seen in FIG. 4, cooperating catch means 114 is showncomprising a pin member 116 projecting from the side 64 of the pitmanmember 60 and a groove 118 formed in the side piece 44 of the ram member48. The

6 pin member 116 is preferably disposed slightly above the groove 118 asin the preferred arrangement of the cooperating catch means 92 of FIG.2.

Reference is now directed to FIGS. 5-7, inclusive, wherein there isillustrated a cooperating catch means 120 of an alternativeconfiguration. As best shown in FIG. 7, the cooper-ating catch means 120comprises an L-shaped finger 122 depending from the lower end 66 of thepitman member 60 and an L-shaped recess 124 formed in a lower portion126 of the ram member 48. The L-shaped finger 122 has a laterallyextending terminal portion 128 positioned to be received in a lateralrecess portion 130 of the L-shaped recess 124.

As shown in FIG. 5, the eccentric rotary means 82 is disposed in its topdead center position. The L-shaped finger 122 is positioned with respectto the pitman member 60 such that the ram member 48 is movablevertically to position the punch bit (not shown) relative to aworkpiece. The throat or entrance 132 of the L-shaped recess 124 has awidth sufficient to permit lateral movement of the pitman member 60during the first half of a cycle of operation, that is, during which theeccentric rotary means 82 is rotated through In FIG. 6, the eccentricrotary means 82 has been rotated through 225 angular degrees and isdisposed in a position corresponding to the position of the eccentricrotary means 82 in FIG. 3E. At this time, the laterally extendingterminal portion 128 of the L-shaped finger 122 has moved into thelateral recess portion 130 of the L- shaped recess 124 to connect thepitman member 60 to the ram member 48. Continued rotation of theeccentric rotary means 82 to its top dead center will cause the pitmanmember 60 to raise the ram member 48 to its initial elevated position.Thereafter, the laterally extending terminal portion 128 will bedisengaged from the lateral recess portion 130 and the ram member 48will, again, be free for vertical movement.

Although the present invention has been shown in connection with certainspecific embodiments, it will be readily apparent to those skilled inthe art that various changes in form and arrangement of parts may bemade to suit requirements without department from the spirit and scopeof the invention.

I claim as my invention:

1. In apparatus having a ram member including one end adapted to performa work-operation on a workpiece disposed adjacent thereto, and a framesupporting said ram member for reciprocal movement wherein during onecycle of operation, said ram member is movable in one direction during apower stroke and in the opposite direction during a return stroke, theimprovement comprising: said ram member having a generally rectangularopening whose periphery is defined by opposed side faces and upper andlower end faces; a pitman member residing within said opening and havinga generally rectangular configuration corresponding to the configurationof said opening; eccentric rotary means slidably engaged with saidpitman member for moving the same in a circular path and, hence,sequentially toward one of said side faces and then into engagement withsaid lower end face during said power stroke, and then toward the otherof said side faces during said return stroke; said pitman member beingsmaller than said opening and having sides which are spaced from thecorresponding side faces of said opening when said pitman member is in acentered position relative to said opposed side faces, said ra-m memberbeing freely movable in its direction of reciprocation whereby theposition of said ram member relative to said workpiece may be adjustedprior to said power stroke; cooperating catch means operable only duringthe said return stroke for moving said ram member in said oppositedirection; and drive means including actuating means for rotating saideccentric rotary means through a single revolution and, hence, formoving said ram member through a single reciprocation.

2. The improvement as defined in claim 1 wherein said cooperating catchmeans comprises a projection on one said member and a catch on the othersaid member, said catch being positioned for engagement by saidprojection during movement of said pitman member in said oppositedirection.

3. The improvement as defined in claim 1 wherein said cooperating catchmeans comprises a pin projecting from one said member toward the othersaid member, the other said member having a notch positioned to receivesaid pin during movement of said pitman member in said oppositedirection.

4. The improvement is defined in claim 1 wherein said pitman member hasan arcuate corner adjacent said c0- operating catch means, said arcuatecorner engaging said other of said side faces and permitting said pitmanmember to rotate about the axis of said eccentric rotary means in theevent said cooperating catch means does not connect said pitman memberto said ram member.

5. The improvement as defined in claim 1 including adjustable springmeans acting on said ram member and said frame for counterbalancing theweight of said ram member whereby said ram member remains in itsadjusted position.

6. The improvement as defined in claim 1 wherein said cooperating catchmeans comprises an L-shaped finger depending from said pitman member andan L- shaped recess formed in a bottom portion of said ram member andpositioned for engagement by said L-finger during movement of saidpitman member in said opposite direction.

References Cited UNITED STATES PATENTS 732,101 6/1903 Morris 83-5541,076,163 10/1913 Shirley 100292 1,597,138 8/1926 Zimmer 83-5543,273,491 9/1966 Calvert 100-53 FOREIGN PATENTS 140,630 4/ 1920 GreatBritain.

BILLY I. WILHITE, Primary Examiner.

1. IN APPARATUS HAVING A RAM MEMBER INCLUDING ONE END ADAPTED TO PERFORM A WORK-OPERATION ON A WORKPIECE DISPOSED ADJACENT THERETO, AND A FRAME SUPPORTING SAID RAM MEMBER FOR RECIPROCAL MOVEMENT WHEREIN DURING ONE CYCLE OF OPERATION, SAID RAM MEMBER IS MOVABLE IN ONE DIRECTION DURING A POWER STROKE AND IN THE OPPOSITE DIRECTION DURING A RETURN STROKE, THE IMPROVEMENT COMPRISING: SAID RAM MEMBER HAVING A GENERALLY RECTANGULAR OPENING WHOSE PERIPHERY IS DEFINED BY OPPOSED SIDE FACES AND UPPER AND LOWER END FACES; A PITMAN MEMBER RESIDING WITHIN SAID OPENING AND HAVING A GENERALLY RECTANGULAR CONFIGURATION CORRESPONDING TO THE CONFIGURATION OF SAID OPENING; ECCENTRIC ROTARY MEANS SLIDABLY ENGAGED WITH SAID PITMAN MEMBER FOR MOVING THE SAME IN A CIRCULAR PATH AND, HENCE, SEQUENTIALLY TOWARD ONE OF SAID SIDE FACES AND THEN INTO ENGAGEMENT WITH SAID LOWER END FACE DURING SAID POWER STROKE, AND THEN TOWARD THE OTHER OF SAID SIDE FACES DURING SAID RETURN STROKE; SAID PITMAN MEMBER BEING SMALLER THAN SAID OPENING AND HAVING SIDES WHICH ARE SPACED FROM THE CORRESPONDING SIDE FACES OF SAID OPENING WHEN SAID PITMAN MEMBER IS IN A CENTERED POSITION RELATIVE TO SAID OPPOSED SIDE FACES, SAID RAM MEMBER BEING FREELY MOVABLE IN ITS DIRECTION OF RECIPROCATION WHEREBY THE POSITION OF SAID RAM MEMBER RELATIVE TO SAID WORKPIECE MAY BE ADJUSTED PRIOR TO SAID POWER STROKE; COOPERATING CATCH MEANS OPERABLE ONLY DURING THE SAID RETURN STROKE FOR MOVING SAID RAM MEMBER IN SAID OPPOSITE DIRECTION; AND DRIVE MEANS INCLUDING ACTUATING MEANS FOR ROTATING SAID ECCENTRIC ROTARY MEANS THROUGH A SINGLE REVOLUTION AND, HENCE, FOR MOVING SAID RAM MEMBER THROUGH A SINGLE RECIPROCATION. 